If you want to detect different types of gases, you will need sensors. If you need any data on the sensitive material then, the Waveshare MQ-135 Gas sensor s a quite good solution.

The MQ-135 sensor is a gas sensor module that incorporates MQ-135, designed for air quality monitoring. It can be used to measure benzene, alcohol, smoke, then generate digital signals for triggering air treatment devices. The MQ-135 is used in Air quality Monitor in consumer and industry applications, this sensor is suitable for detecting benzene, alcohol, smoke. Avoid the noise of LPG, natural gas, coal gas. The sensitivity can be adjusted by the potentiometer.MQ-135 gas sensor applies SnO2 which has lower conductivity in the clear air as a gas-sensing material. In an atmosphere where there may be polluting gas, the conductivity of the gas sensor raises along with the concentration of the polluting gas increases

The sensitive materials of the MQ-135 gas sensor are benzene, alcohol, and smoke. When the target combustible gas exists, The sensors conductivity is higher along with the gas concentration rising. Please use a simple electro circuit, Convert the change of conductivity to the corresponding output signal of gas concentration.

Application :

Air quality monitor

Features:

1. Sensitive for benzene, alcohol, smoke
2. Output voltage boosts along with the concentration of the measured gases increases
3. Fast response and recovery
4. Adjustable sensitivity
5. Signal output indicator

Package Includes:

1 x Waveshare MQ-135 Gas Sensor